George Mitchell (pictured, d. 2013) helped develop the hydraulic fracturing technique for unearthing natural gas shale, which led to more energy fortunes. He was the first to develop the Barnett shale field in Texas, which he later sold to Devon Energy in 2002 for $3.5 billion. During a so-called retirement, Mitchell turned to real estate and bought Bald Head Island in North Carolina along with hotels in Galveston. In Houston, though, he is probably best known for creating the Woodlands.

Thomas Friedkin, the former Hollywood stunt man with 11 movies to his name, founded Gulf States Toyota in 1969. It quickly rose to prominence, probably thanks in part to its exclusive distribution rights in five states. The company now does $7 billion in sales.

The late Ting Tsung "T.T." Chao moved his family to America from Taiwan in the 1980s, where they quickly began acquiring chemical plants in the United States southeast corridor. These plant acquisitions eventually became Westlake Chemical Corp., which is now North America's largest low density polyethylene manufacturer (a component which is used in milk and juice cartons, produce bags and plastic wrap.) Pictured above is T.T.'s son Albert, who serves as CEO.

Dan Duncan, pictured in this 2010 file photo, is a rags-to-riches story. He was born poor in Center, Texas and was raised by his grandmother by age 7 after his mother and brother died. He would later make it big in natural gas, oil and petrochemical pipelines. Upon his death, he left his nearly $10 billion estate to his four children. Two of his daughters, Milane and Dannine, are active philanthropists around Texas.